diff --git a/go/engine/loop.go b/go/engine/loop.go
index b535891..d151c72 100644
--- a/go/engine/loop.go
+++ b/go/engine/loop.go
@@ -5,11 +5,11 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"os"
+	"io"
 	"strings"
 )
 
-func Loop(startSym string, en *Engine, ctx context.Context) error {
+func Loop(en *Engine, startSym string, ctx context.Context, reader io.Reader, writer io.Writer) error {
 	err := en.Init(startSym, ctx)
 	if err != nil {
 		return fmt.Errorf("cannot init: %v\n", err)
@@ -20,9 +20,9 @@ func Loop(startSym string, en *Engine, ctx context.Context) error {
 	fmt.Println(b.String())
 
 	running := true
+	bufReader := bufio.NewReader(reader)
 	for running {
-		reader := bufio.NewReader(os.Stdin)
-		in, err := reader.ReadString('\n')
+		in, err := bufReader.ReadString('\n')
 		if err != nil {
 			return fmt.Errorf("cannot read input: %v\n", err)
 		}
@@ -33,7 +33,9 @@ func Loop(startSym string, en *Engine, ctx context.Context) error {
 		}
 		b := bytes.NewBuffer(nil)
 		en.WriteResult(b)
-		fmt.Println(b.String())
+		//fmt.Println(b.String())
+		writer.Write(b.Bytes())
+		writer.Write([]byte{0x0a})
 	}
 	return nil
 }
diff --git a/go/resource/fs.go b/go/resource/fs.go
index 8d91039..585ca3b 100644
--- a/go/resource/fs.go
+++ b/go/resource/fs.go
@@ -44,7 +44,7 @@ func(fs FsResource) FuncFor(sym string) (EntryFunc, error) {
 		return fn, nil
 	}
 	_, err := fs.getFuncNoCtx(sym)
-	if err != nil {
+	if err == nil {
 		return nil, fmt.Errorf("unknown sym: %s", sym)
 	}
 	return fs.getFunc, nil
diff --git a/go/state/state.go b/go/state/state.go
index 5f21436..cc2c759 100644
--- a/go/state/state.go
+++ b/go/state/state.go
@@ -266,6 +266,7 @@ func(st *State) Up() (string, error) {
 	if len(st.execPath) > 0 {
 		sym = st.execPath[len(st.execPath)-1]
 	}
+	log.Printf("execpath %v", st.execPath)
 	st.sizeIdx = 0
 	return sym, nil
 }
diff --git a/go/vm/input.go b/go/vm/input.go
index cfa0c47..9245bdf 100644
--- a/go/vm/input.go
+++ b/go/vm/input.go
@@ -11,10 +11,10 @@ import (
 var (
 	inputRegexStr = "^[a-zA-Z0-9].*$"
 	inputRegex = regexp.MustCompile(inputRegexStr)
-	ctrlRegexStr = "^[<>_]$"
-	ctrlRegex = regexp.MustCompile(inputRegexStr)
+	ctrlRegexStr = "^[><_]$"
+	ctrlRegex = regexp.MustCompile(ctrlRegexStr)
 	symRegexStr = "^[a-zA-Z0-9][a-zA-Z0-9_]+$"
-	symRegex = regexp.MustCompile(inputRegexStr)
+	symRegex = regexp.MustCompile(symRegexStr)
 
 )
 
diff --git a/go/vm/runner.go b/go/vm/runner.go
index 89c44fc..e58a69f 100644
--- a/go/vm/runner.go
+++ b/go/vm/runner.go
@@ -255,16 +255,19 @@ func(vm *Vm) RunInCmp(b []byte, ctx context.Context) ([]byte, error) {
 		return b, nil
 	}
 
-	log.Printf("input match for '%s'", input)
+	log.Printf("input match for '%s', target '%s'", input, target)
 	_, err = vm.st.SetFlag(state.FLAG_INMATCH)
 
-	sym, _, err = applyTarget([]byte(target), vm.st, ctx)
+	target, _, err = applyTarget([]byte(target), vm.st, ctx)
+	if err != nil {
+		return b, err
+	}
 
 	code, err := vm.rs.GetCode(target)
 	if err != nil {
 		return b, err
 	}
-	log.Printf("loaded additional code: %x", code)
+	log.Printf("loaded additional code for target '%s': %x", target, code)
 	b = append(b, code...)
 	return b, err
 }
diff --git a/go/vm/runner_test.go b/go/vm/runner_test.go
index d509206..c4f5591 100644
--- a/go/vm/runner_test.go
+++ b/go/vm/runner_test.go
@@ -185,7 +185,6 @@ func TestRunReload(t *testing.T) {
 		t.Fatal(err)
 	}
 	r, err := vm.Render()
-//	r, err := pg.Val("dyn")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -199,14 +198,6 @@ func TestRunReload(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-//	r, err = pg.Val("dyn")
-//	if err != nil {
-//		t.Fatal(err)
-//	}
-//	log.Printf("dun now %s", r)
-//	if r != "baz" {
-//		t.Fatalf("expected result 'baz', got %v", r)
-//	}
 }
 
 func TestHalt(t *testing.T) {
@@ -373,3 +364,38 @@ func TestRunMenuBrowse(t *testing.T) {
 	}
 }
 
+func TestRunReturn(t *testing.T) {
+	st := state.NewState(5)
+	rs := TestResource{}
+	ca := cache.NewCache()
+	vm := NewVm(&st, &rs, ca, nil)
+
+	var err error
+
+	st.Down("root")
+	st.SetInput([]byte("0"))
+	b := NewLine(nil, INCMP, []string{"0", "bar"}, nil, nil)
+	b = NewLine(b, HALT, nil, nil, nil)
+	b = NewLine(b, INCMP, []string{"1", "_"}, nil, nil)
+	b = NewLine(b, HALT, nil, nil, nil)
+
+	ctx := context.TODO()
+
+	b, err = vm.Run(b, ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	location, _ := st.Where()
+	if location != "bar" {
+		t.Fatalf("expected location 'bar', got '%s'", location)
+	}
+	st.SetInput([]byte("1"))
+	b, err = vm.Run(b, ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	location, _ = st.Where()
+	if location != "root" {
+		t.Fatalf("expected location 'foo', got '%s'", location)
+	}
+}